Material handling system



July 29, 1952 w. A. GRUENEBERG 2,605,004

MATERIAL HANDLING SYSTEM Filed Sept. 16, 1947 s Sheets-Sheet 1 JNVENTOR. WALT": A. G RULNEBERQ ,4 7' TORNE V July 29, 1952 w. A. GRUENEBERG MATERIAL HANDLING SYSTEM 8 Sheets-Sheet 2 Filed Sept. 16 1947 M LP INVENTOR. WALTER A. GRUENEBERQ ATTORNEY y 29, 1952 w. A. GRUENEBERG 2,605,004

MATERIAL HANDLING SYSTEM WALTER A. GRUENEBERG ATTORNEY 8 Sheets-Sheet 5 INVENTOR.

ATTORNEY I I I06 I H08 W.A. GRUENEBERG MATERIAL HANDLING SYSTEM fk ISA-"* WALTER A. GRUENEBERG July 29, 1952 Filed Sept. 16, 1947 July 29, 1952 w. A. GRUENEBERG MATERIAL HANDLING SYSTEM 8 Sheets-Sheet 6 Filed Sept. 16, 1947 INVENTOR. WALTER A. GRUENEBERG, 4

y 29, 1952 w. A. GRUENEBERG 2,605,004

MATERIAL HANDLING SYSTEM v y 29, 1952 w. A. GRUENEBERG 2,605,004

MATERIAL HANDLING SYSTEM Filed Sept. 16, 1947 8 Sheets-Sheet 8 EBE RG WALTER A. GRucN A rraR/vsy Patented July 2 9, 1952 MATERIAL HANDLING SYSTEM Walter A. Grueneberg, Saginaw, Mich., assignor to Jackson &

Church Company,

Saginaw,

Mich., a corporation of Michigan Application September 16, 1947, Serial No. 774,194

4 Claims. (Cl. 2141) 7 The present invention relates to a material handling system which is particularly but not exclusively adapted for receiving newly molded concrete building blocks from a block-making machine and for conveying the blocks to storage or treating kilns.

Among the objects of the present invention are toprovide an improved material handling system which is particularly but not exclusively adapted for use with brick or concrete block-making equipment wherein bricks, concrete blocks, and the like are manufactured by continuous mass production methods involving a continuous flow of material from the raw material stockpiles, through the mixing apparatus, the block-molding machine, and to the final block curing kilns and storage yards; and in particular to provide such a material handling system wherein the newly formed blocks or the like are economically and speedily conveyed from the block-making machineto the curing kilns and/or storage yards by automatic and semi-automatic processes and with the minimum of handling.

Another object of the present invention is to provide an improved continuously operative oonveying system wherein an empty tram conveyor is automatically loaded at a loading position with blocks from a block-making machine andlconveyed'therefrom along tram rails, being automatically replaced at the loading position by ann other empty tram conveyor.

Another object is to provide an improved conveyor system of the character described wherein the tram conveyor provides a plurality of blockreceiving shelves arranged in vertical tiers, the empty tram conveyor being conveyed along tram rails to an automatically operated conveyor handling mechanism which maneuvers the tram conveyor to a block loading position adjacent a blockmaking machine, whereat said shelves are successively loadedautomatically with newly-formed blocks, the block loading tram conveyor being thenautomatically hoisted to an elevated end of an-inclined tra-m rail along which the tram conveyor rides to said curing kilns and/or storage yards.

Other objects of this invention will appear in the following description and appended claims, reference being had to the accompanying drawings forming a part of this specification wherein 2 like reference characters designate corresponding parts in the several views. 1

In the drawings: q 7 Fig. 1 is essentially a schematic side. view. partially in section and with portions broken,

away, showing a material handling systememe.

ploying the present invention. Q a

Fig. 2 is essentially a schematic plan view of the system shown in Fig. 1, showing also a portion of the tracks leading to the storage yards:

Fig. 3 is a fragmentary enlarged bottom view showing the conveyor at the loading position andbeing taken in the direction of the arrows essentially along the line 33 of Fig. 1, the support-; ing structure for the block loading conveyor belt: being removed. q

Fig. 4 is an enlarged side view of the conveyor; in the block loading position within the conveyor handling frame, taken substantially along 11 line 4-4 in the direction of the arrows of Fig. 2, the block loading conveyor belt and thedischarge tram rail beingremoved. g g N Fig. 5is essentially an enlarged fragmentary, end view of the lower portion of the conveyor and conveyor handling frame takenfrom the letter id:

. of Fig. 4..

Fig. .6 is essentially an enlarged: fragmentary end view of the upper portion of the conveyor nd conveyor handling frame taken from the left, end

of Fig. 4, portions of the hoist mechanism bein g" broken away and sectioned to show details of construction, and portions of one of thehoisting shafts being broken away to show section'ali. de'-' tails of the hoist control shaft, the traversing motor and support therefore being removed. 1,;

Fig. '7 is essentially an enlarged fragmentary top view of the right hand portion-of the conveyor and conveyor handling frame shown in Fig.4,the pneumatic cylinder and push-oil mechanisrn be ing removed.

Fig. 8 is essentially an enlarged fragmentary top view of the left hand portion of theconveyor and conveyor handling frame shown in -Fig. l. the conveyor being shown in phantom in the initialentering position.

Fig. 9 is a schematic plan of electrical circuits suitable for use with the present invention.

Before explaining the present inventionin e: tail, it is to be understood thatthe, invention, is not limited in its application to the.,details;;of

construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

Section I .Geneml In brief, the present invention provides an automatic conveyor means whereby newly formed building blocks may be received directly from a block molding machine and conveyed to treating kilns or storage. To this end, a number of tram carriers or conveyors, each having a plurality of block carrying shelves arranged one above another for receiving the newly formed blocks from the block-molding machine, are provided for riding along a tram rail between a conveyor handling frame and the said storage or treating kilns. The conveyor handling frame provides a mechanism for maneuvering each conveyor in turn to a loading position adjacent the block-molding machine.

Thus an empty conveyor returning from the storage or treating kilns rides along a return tram rail to its entering position within the conveyor handling frame, from whence a traversing mechanism provided by the handling frame automatically moves the conveyor to its loading position within the handling frame whereat the conveyor is then automatically loaded with blocks from the block-molding machine. The conveyor handling frame supports the carrier in its proper loading position during the loading operation and also provides a hoist mechanism for automatically raising the conveyor successively through vertical increments equal to the spacing between the said conveyor shelves as each shelf is loaded, permitting selective vertical alignment of each shelf in its turn at the proper level to receive the newly-formed blocks on their pallets from a chain conveyor, directly as they are stripped from the block-making machine.

The fully loaded conveyor is then hoisted by the handling frame to an elevated position of an outgoing tram rail from whence it runs by gravity alongthe tram rail to the storage or treating kilns. An empty conveyor returned by the return tram rail from the storage or treating is then automatically received by the handling frame and the above outlined process is repeated.

Figs. 1 and 2 show a schematic plant layout for manufacturing building units, such as concrete blocks, and employing a particular arrangement by way of example of a conveyor system embodying the present invention. Letters of the alphabet are utilized primarily to indicate generally the major features of the conveyor system disclosed herein, which usually comprise a multiplicity of parts and details indicated by numerals.

The tram conveyor handling frame A is shown with a tram conveyor B in the loading position adjacent the concrete blocking-molding machine C. The block-molding machine C may be any one of numerous conventional block-making machines, although the present invention operates particularly successfully with the block-moldin machine described in my co-pending application bearing Serial No. 688,118, now Patent No. 2,598,254.

Aggregate from the pit D is conveyed by the continuous bucket elevator E to the receivin hopper F where water and cement are added in zontal shelves J, Figs. 1, 3, and 4, comprised of horizontal, longitudinally extending, paired T- beams arranged one above another in tiers along opposite sides of the conveyor B and having shelf portions 25, Fig. 5, which extend inwardly from opposite sides of the conveyor B. The conveyor chain I extends within the open front end of the conveyor B, slightly above the uppermost horizontal shelf J when the conveyor B is in its initial loading position, Fig. 1. The ends of the molded blocks H on the conveyor chain I overhang the sides thereof, Fig. 3, and also overlie the shelf portions 25 as shown by the phantom view of the block H in Fig. 5.

The blocks H are preferably discharged to the conveyor chain I from the machine C and advanced into the framework of the conveyor B on the conveyor chain I one by one as they are molded. When the chain conveyor I is completely loaded so that blocks H overlie the inwardly extending shelf portions 25 along essentially the entire length of the top shelf J, the conveyor B is automatically hoisted through a vertical increment equal to the vertical spacing between the shelves J. The blocks H are thus unloaded from the chain conveyor I to the top shelf J, and the second shelf J from the top is elevated to the position immediately below the chain conveyor I formerly occupied by the top shelf J, so as to receive the next load of blocks H from the chain conveyor I upon the next automatic increment of hoisting of the conveyor B. Finally when each shelf J is loaded, the loaded conveyor B is raised to the upper portion of the handling frame A and is pushed off onto the upper portion of the inclined track K.

The loaded conveyor B rolls by gravity down the inclined track K to the paired transverse rails L provided for the one or more bridge cranes M. Each bridge crane M provides a short bridgetrack section, which may be aligned with the lower end of the track K to receive a loaded conveyor B therefrom, and which travels on its tracks L transversely to the tracks K and N to selectively align its bridge-track section with one of the parallel track portions N. The tracks N pass through the steam treating kilns O and lead to the paired transverse tracks P for the bridge cranes Q, which latter are similar in operation and function to the bridge cranes M and provide means for transferring the loaded conveyors B as they emerge from the steam kilns O, to one of the parallel tracks R which leads to the storage yards, and for transferring the empty conveyors B, as they return from the storage yards, to the empty-conveyor return tracks S. The empty conveyors B are then transferred by the bridge cranes M from the tracks S to the return track T, along which they are carried by the power driven belt means U to a walking beam escapement mechanism V adjacent the receiving side of the conveyor handling frame A.

The escapement mechanism V holds all the empty conveyors B as they are returned from the storage yards and dispenses them in their order of arrival one at a time as required into the handling frame A.

- At the proper time when the handling frame A is in readiness to receive another empty conveyor B, the automatic escapement mechanism V is actuated to released the foremost empty conveyor B, which then rolls into the receiving portion of the frameA and is automatically moved by a traversing mechanism provided thereby to the lower forward loading position, Figs. 1, 2, and 4. Thus a complete cycle in the operation of a conveyor B, from the loading position adjacent the molding machine 0, through the curing kilns O, to storage R, back to the loading position at the handling frame A, is completed.

Section II.-The block: conveyor Details of a particular embodiment of aconveyor B embodying the present invention are shown by way of example in Figs. 3, 4, and 5. The empty conveyor B enters the handling frame A at the rear and lower left thereof by way of the track T, Figs. 4 and 5, and is then'maneuvered by a traversing mechanism provided by frame A to an initial loading position at which it is shown, lower right, Fig. 4. The frame A holds the conveyor B in the loading position until the latter is fully loaded. The loaded conveyor B is then elevated by a hoist mechanism also provided by the frame A to an exit position, upper right, Fig. 4, from whence the loaded conveyor B leaves the frame A by way of the tram rail K as above outlined.

The conveyor B is shown supported by two pairs of tram wheels 25 on the section of track 21 which is provided by the hoist mechanism of the frame A. The four wheels 25 are paired at opposite sides of the top portion of the'conveyor B, each pair of wheels 26 being journaled in one of a pair of wheel supporting forks 23, which latter are secured to the transverse beam 29 near its opposite ends. The beam 29 is also secured at opposite ends to the pair of parallel beams 32, which in turn are secured to the top structure of the conveyor B along its opposite sides. The body of the conveyor B comprises an essentially retangular frame structure preferably of angle and channel beams and having two parallel Vertical sides formed from six upright supporting beams 33 distributed at the upright corner edges and at essentially the midportions of the two broader sides, Figs. 4 and 5. The two upper horizontal corner edges comprise the beams 34 joined at opposite ends to the corner uprights 33.

The aforesaid shelves J comprise the five pairs of horizontal T-beams secured to the uprights 33 within the interior broader sides of the conveyor B and having the inwardly extending shelf portions 25 which are conveniently spaced vertically to provide room for a horizontal row of blocks H on each shelf J.

At the back of the conveyor B, Fig. 4, are two horizontal cross braces 35 disposed between the back uprights 33. The corresponding space at the front or block receiving end of the conveyor Bis unobstructed to permit entry of the conveyor chain I. Likewise the bottom of the conveyor B is also open to permit the hoisting of the latter above the chain conveyor 1. Whererequired for additional reinforcement, the conveyor B provides a plurality of horizontal and vertical reinforcing'plates 36 at the various junctures of the above mentioned beams and braces. v

Section IIL The conveyor handling frame Details of a particular embodiment of the conveyor handling frame A are shown by way of example in Figs l through 8 wherein a steel trestle work is shown for supporting the automatic mechanism for handling the block carry- 42, and 43 rest upon supporting footings 44, arejoined near their bases by the longitudinal horizontal reinforcing beam 45, and are joined and supported at their upper ends by the longitudinal horizontal reinforcing beam 46.,

Three upright load supporting beams 41, 48, and 49 are positioned along the right edge, central portion, and left edge, respectively, Fig. 4, of the broad side of the frame A opposite the conveyor receiving side. The upright beams 41, 48, and 49 also rest upon footings 44, and are joined near their bases and near their upperportions by the longitudinal horizontal channel beams 5| and 52, respectively.

Horizontal transverse beams 53 and 54 are disposed between and secured at opposite ends to the upright beams 41 and 41 to comprise lower and upper transverse braces, respectively, for the block loading end of the frame A. Similarly, lower and upper transverse braces 55 and 56, respectively, are disposed between the upright supports 43 and 49 at the opposite end of the frame A.

The end of the frame A opposite the block oading end, Figs. 5 and 6, is braced by the crossing struts 51 which are secured at their opposite ends by screw-threaded attachments to the uprights 43 and 49 and are adjustable for tension by the turn buckles 58. The opposite or block loading end of the frame A is similarly braced at its upper portion by the adjustable tension struts 59, but the lower portion thereof is open to permit entry of the conveyor chain I and loading of the conveyor B with blocks H.

Opposite the conveyor entering side of the frame A and slightly below the top of the con-' veyor B when the latter is in its initial loading position within the frame A, Fig. 4, is the longitudinal and horizontal channel beam 62'which extends from an attachment at one end with the upright beam 49 to an attachment at the other end with the upright beam 41, being also secured at approximately its midpoint to the upright beam 48. On the conveyor entering side of the frame A and at approximately the same level asv the beam 62 is a similar horizontal channel beam Bl which extends between attachments at opposite ends to the upright channel beams 4| and 42, and accordingly does not extend horizontally across the entire length of the frame A. ,An empty incoming conveyor B may thus enter the frame A between the upright beams 42 and 43 and along the tram rail T, which is'supported from the horizontal beam 63, thelatter being elevated above the horizontal beam,62 and being supported at opposite ends by attachments with the uprights 42 and 43. The various ,junctures between the horizontal and vertical supports of the fram A are suitably reinforced as'required 12y the plurality of vertical and'horizontal plates The railportion 21, which supports the conveyor B and maneuvers the latter through its variiis positions within the frame A, is rigidly secured to; the lower ends of the two threaded hoisting shafts66 by the two collar and nut assemblies 6-1, Fig. 6. The hoisting shafts 66. are depended from the traversing carriage indicated generallyby the letter W for riding therewith and are raised or lowered by operation of the hoist motor-69, Figs. 6 and 7.

By operation of the traversing motor 65 and the sprocket chain. coupled between the motor 65 and the carriage W, the latter is pulled along the rails'IZ and "I3, Figs. 7 and 8. By cooperable action between the traversing motor 65 and the hoistmotor 69, the track portion 2! and a conveyor B suspended therefrom may be raised or lowered or traversed essentially from one end of the frame A to the other. The traversing motor 65 is mounted on the platform I5 which is supported across and secured to the horizontal beams 56 and I6 by the plurality of bolts 11. The beam 16, Fig. 8, extends parallel to the beam 56 and is secured at opposite ends to the horizontal beams 52 and 46.

Acrossthe top of the frame A at the right, Fig. '7, is. the horizontal beam 18 which is supported at its opposite endsby the beams 46and 52 in parallelism with and essentially at the same level as thetransverse horizontal beam 54. The level platform I9for the pulley mounting. 62, which latter provides the bearing 83 for the aXlevs'haft 84,0 the driven pulley sprocket 85,, is supported across thebeams'IS and 54. The. sprocket chain I4 islooped around thesprockets 85 and 81 and completes a continuous loop with the-carriage W to which thechain 'I4 is secured at its opposite endsby the two tension adjustin bolts 86. The driving sprocket 81 is mounted on the motor driven shaft 88 for rotation therewith, the latter being driven by the reversible electric motor 65 to drive the sprocket chain I4 and to pull the" carriage W in one direction or another along the railsj2. and I3;

The rail-l2; isessentially squarev in cross section andstands on one edge to provide an inverted V-rail for interlocking with the two V-type carriage wheels 09 on the left side of the carriage W; Fig. 6, thus preventing accidental lateral movement of-thecarriage W from its tracks. The rail I2 is secured at its opposite ends by bolts 92 to the right angle brackets 93*which reston and are secured to the cross beamsiB-and 16 by the plurality of bolts'94.

The rail I3 provides a conventional flat rail surface for the two cylindrical carriage-wheels 96* at the right side of I the carriage W, Fig. 6, and preferably comprises achannel beam supported} at opposite ends by the transverse beams I6 and I8 to-which itis'secured by the plurality of bolts-95. The wheels 89 and'96 are journaled to the endsof the twoaxle shafts 91 which are supported at theiroppositeends within the rectangular frame 98. The frame 98 com-prises the body of the carriage-W. and is reinforced at its corner portions by theplurality of flat reinforcing-plates il. A platform I02 is supported across and secured tothe frame 96by the bolts I03 and supports the mounting I04 for the hoist mechanism, including the hoist motor 66, the

gear reducer I05, and the hoisting shafts 66. Themounting I04.is securedto theplatform I02, by the plurality of bolts I I.

The hoist motor 69 is preferably a conventional reversible electric motor operatively coupled to theqtubular. shaft I66; for rotation thereof by mansi n eedl educer; Sha t. I 96.; is

journaled in the bearings I01 within the mounting I04 and is keyed to the central gear I08 which drivesthe pair of lateral gears I09. Each gear IDS is keyed to one of each of the two internal screw-threaded bushings; II2 which is journaled in the respective hearing I I3 provided therefor by the mounting I04 and which is in screw driving engagement with one of each of the two screw-threaded hoisting shafts 66. In Fig. 6, the mounting I04 is broken away to show sectional details of the operable coupling between theshaft I06 and the right hoist shaft 66. It isto be understood that essentially the same coupling is also provided for the left shaft 66.

Upon rotation of the shaft I06 by the hoisting motor 69, the internally threaded bushings '2 are rotated to raise or lower the threaded hoisting shafts 66 in accordance with the direction of rotation of the hoist motor 69. Each internally threaded bushing H2 and its corresponding-gear I08 keyed therewith is held against vertical movement by the flange I I4 of the bearing ll3:which fits against the depending shelf or-shoulder II5 of the mounting I04.

Av vertical hoist, control shaft H6, Figs. 4 and 6, is secured at. its upper end to the platform I02 by the plurality of bolts II'I, Fig. 7, and extends downward to. an attachment with the bracket 8 provided by the lower portion of one of the hoisting shafts 66. In Fig. 6, the left hand hoist shaft 66 which provides the bracket H8 is directly in front of the shaft H6 and is shown partially broken away to display sectional details of the hoist control mechanism provided by the shaft H6.

The hoist control shaft H6 provides four inclined slots H9, being one less in number than the number of shelves J provided by the conveyor 13. Within each slot H9 is the pivotally mounted dog I22 which pivots on the pivot pin I23 secured within the shaft H6. The slots H9 are vertically spaced in accordance with the vertical spacing of the'shelves J. Beneath the lowermost dog I22-and spaced therefrom by the ver-' tical distance between the shelves J is the projection I24 of the hoist control shaft H6.

When each dogI22 rests on the inclined base of its corresponding slot H6 at the lower limit of its downward pivotal movement, it projects slightly from its slot H9. The slots II 9 are adapted in size to permit upward pivoting of the dog- I22 sufficiently to withdraw the projections thereof into slots IIB. By operation describedin more detail below, the dogs I22 and the projection I24 cooperate with a set of limit switches in an electrical control system to effect the automatic hoisting operations briefly outlined above.

Along the right side of the frame A, Fig. 5, and at the lower left portions thereof, Fig. 4, area pair of horizontal bumpers I25 which are supported by a plurality of flexible and resilient mountings. The mountings for the upper and lower bumpers I25 are essentially similar but inverted with respect to each other.

Each bumper mounting includes an angle bracket I21, which is secured to its respective bumper I25 and is also secured. to a pivot arm I28, thelatter being pivotally mounted at I29 to a. pivot bracket I32. The pivot brackets I32 for the .upperand lower bumpersare secured to the horizontal beams 62 and EI, respectively, and are reinforced by webs I34 and I35., Projeoting. spring pilots I36 are provided by the brackets I21 and I33 for the coil springs.l3'l

which providearesilient backingforthebumpers I25. A bumper movement limiting arm I38 is pivotally secured at I39 to each pivot arm I28 and is extended through an opening provided therefor in the corresponding bracket I33.- The shoulder I42 of each arm I38 limits movement of the bumpers I25 against the tension of the springs I31 by contact with the brackets I33. Adjustment of the position of the bumpers I25 is permitted by the adjusting nuts I43 which are screw-threaded on the ends of the arms I38 projected through the brackets I33. As the empty conveyor B returned from the storage yards is released from the tramrail T into the hoist frame A by the automatic walking beam escapement mechanism V, the impact of the conveyor B is absorbed by the resiliently mounted bumpers I 25.

When the conveyor B comes to rest Within the frame A at its entering position on the track portion '21, the carriage W is then automatically moved to the loading position at the right, Fig. 4. A pair of horizontal guide bars I44, on opposite sides of the conveyor B and supported by the frame A, accurately guide the conveyor B to its loading position. The ends I45 of the guide bars I44 are flared outwardly to receive the conveyor B as it is moved by the traversing motor 65 from the entering position to the loading position.

Each bar I44 is supported by a plurality of supporting structures, four in the present example, comprising the laterally adjustable screwthreaded rods I46 and the webbed brackets I41. The brackets I41 which support the guide bar I44 along the left side of the conveyor B, Fig. 5, are secured to and supported by the horizontal beam 6|. The corresponding brackets I41 on the other side of conveyor B are secured to and supported by the horizontal beam 62. Each threaded rod I46 is adjustably secured by the double adjusting nuts I48 to an upright boss I49 provided by the bracket I41, permitting lateral adjustment of the spacing between the guide bars Section IV.Limit switches The automatic operation of the present invention is effected by an electrical control circuit, Fig. 9, which is controlled by the opening and closing of a system of limit switches in accordance with the operation of the above described apparatus. As the empty incoming conveyor B rides on the track portion 21 of the hoisting mechanism and comes to rest against the bumpers I25, the cross beam 29 of the conveyor B strikes the normally open limit switch II which is supported from the horizontal beam 62 by the bracket I52, Fig. 5. The closing of limitswitch I 5! energizes the traversing motor 65 to drive the carriage W and the conveyor B supported therefrom on the track 21 to the loading position at the right in Fig. 4.

The limit of the travel of the conveyor B to the right is determined by the limit-switch I53, Fig. 7, which is supported from the rail 13 by the bracket I54 and is tripped by the frame 98 of the carriage W when conveyor B reaches its loading position.

As the molded blocks H progress one by one toward the leftward extremity of the conveyor chain I, the foremost block H finally trips the limit switch I55, mounted upon the end of the support for the conveyor chain I, Fig. 3, and the hoist motor 69 is operated to raise the conveyor B and thereby to unload the blocks H from the motor 69 stops when the uppermost projecting dog I22 trips the limit switch I56, Fig. 6, supported from the mounting I04.

The above outlined hoisting and shelf loading procedure is repeated four more times, loading each shelf J in turn. On the last hoisting operation, the conveyor B is raised until the track portion 21 aligns with the upper portion of the inclined tram rail K which is supported from the beam 52. In this position of the hoisting mechanism, both limit switches I56 and I51 are tripped by the projection I24, Fig. 6, and. the hoist motor 69 again stops. switch I51, secured to the mounting I64, energizes an electrically controlled air valve, not shown, which actuates the pneumatic ram I58, Fig. 6. The pneumatic ram I58 is supported by the beam I59, which extends across the top portion of the frame A and is supported at one end from the horizontal beam 52 by the bracket I62. The other end of the beam I 59 is supported from the horizontal beam 46 by the bracket I63.

The pneumatic ram I58 provides the plunger rod I64 which is secured to the right end, Fig. 4, of the arcuate arm I65. The left end of the arm I65 provides the push-ofi rod I66 which extends.

through and is slidably mounted within an open-- ing I61 provided therefor within the said left end of the arm I65. The right end of the push-off rod I66 in Fig. 6 is in alignment with and ad- J'acent the conveyor beam 29, when the track 21 is at its elevated position in alignment with the track K, and provides the spring retaining flanged head" I68 for the coil spring I 69. The spring I69 is compressed between the flanged head I68 and the arm I65 to resiliently hold the push-off rod I 66 to the right in Fig. 6 and to absorb the shock of impact when the conveyor B is pushed from the hoisting frame A upon actuation of the ram I58. The opposite end ot the rod I66 extends from the other end of the. opening I61 and is threaded to receive the re-- taining nuts I12 which hold the rod I66 in place. within the opening I61 against the force ofthe spring I69. 4

Upon tripping limit switch I51 and actuating hydraulic ram I58, the plunger arm I 64 forces the flanged head I 68 against the adjacent end of beam 29, pushing the loaded conveyor B on the track K along which it rides by gravity to the treating kilns as previously described. The limit of the stroke of the plunger arm I64 is deter mined by the limit switch I13, which is supported from the beam I59 by the bracket I14 and which is tripped by the arm I65 as the latter moves to the right, Fig. 6. The tripping of limit switch I 13 de-energizes the above mentioned electrically controlled valve for the pneumatic ram I58, causing retraction of plunger I64.

The tripping of limit switch I13 also energizes the traversing motor 65 to move the carriageW to the left in Figs. 7 and 8. At approximately the midpoint of the leftward movement of the carriage W, limit switch I15, supported from the rail 13 by the bracket I16, Figs. 4 and 6, is tripped by contact with the end of the beam 29, energizing the hoist motor 69 to lower the hoisting shafts I66 and the track portion 21 supported thereby. It is to be noted in this connection that the dogs I 22 may freely pivot upward Without tripping the limit switch I56 as the hoist control shaft H6 is lowered.

At the end of the desired leftward movement of the carriage W, limit switch I11, supported Tripping of limitv from the rail "I3 by the braclret Ii8, is tripped by an unde'rportion of the carriage W and the traversingmotor 65 is stopped. When the track portion 2'! is lowered by operation of the hoist motor 59" to a position level with the incoming track '11, theuppermost portion of the hoist control shaft I IE will have been lowered below the limit switch I'I-B', secured to the mounting I04, thereby releasing the limit switch I19 and stopping the hoi'stmotor 69.

Section. V.-Opemtion A summary of the operation of the present invention may be best presented in connection with the schematic plan of the electrical circuits, Fig. 9, which cooperate with the above described structure to efiect' its automatic. operation. The motors 65 and 09' for the horizontal and vertical movements respectively of the track portion 21 are preferably conventional reversible electric motors connected with a 220-volt' power source I82, for example. Upon closing the three nor mally open left relay switches I83, the motor 65 is caused to turnin one direction to move the traversing-carriage W to the left. Upon opening switches I83 and closing thethree normally open right relay switches Iiid, the motor 65 is reversed and the traversing carriage W is moved to theright.

Similarly closing the three normally open .up" relay switches I85 will cause operation of the hoist motor 68 to raise the track 2'I. Closing the three normally open clown relay switches I86 and-opening relay switches I85 will reverse the hoist motor 89 and lower the track 2?. Overload circuit breakers'or fuses I87 and I88 are in the circuits for the motor 65 and 69 respectively.

A 110-volt power source I89 may suitably be employed to power the control circuits through the three-position selector switch I92, which may be set at the OK position 1 to disconnect the control circuit from its power source I89. the "automatic position 2 to permit automatic operation of the electrical controls, or the manual position 3 to permit manual operation of the controls. It is to be noted that the normally open relay switch I93, in series with the selector switch I92, is operated from relay I94 in the circuit I95 for the pump motor, not shown, which supplies pressur to the pneumatic ram I58. Thus the control circuits of Fig. 9 cannot operate until thepneumatic pump circuit I95 has been previously closed.

In Fig; 9, selector switch I92 is set at position 2 for automatic operation of the control circuits. All limit switches and all relay switches are shown in their normal open or closed positions before a conveyor B is inthe conveyor handling frame A and before electric current is supplied to the control circuits. We shall assume that no conveyor B is in the frame A, that an empty conveyor B is held at the end of the track T in readiness to ride on the track portion 27 under gravity upon being released by the walking beam escapement mechanism V, and that relay switch I93 is closed.

The escapement mechanism V is adapted to block any number of conveyors B from enterin the frame A, but is actuated to release a single empty conveyor B to the frame A when solenoid I95 is energized. As may be observed from Fig. 9, solenoid I96 cannot be energized until all three switches I01, IT'IA, and IIA are closed. Relay switch I91 is normally closed unless relay 202 is energized. Since the energizing of relay 202 also closes relay switches I86, which operates 12 hoist motor 69 to lower the track 21,, switch I9! will not prematurely close while the track 21 is still being lowered to the level of the incoming track T.

The normally open switch I-I'IA' is closed when limit switch I'II is tripped, i. e., when the carriage W has reached the extreme leftward extent of its travel in Fig. l. Switch IS'IA is normally closed unless limit switch I51 is tripped, i. e., when a conveyor B is already in position on track 2! and resting against the bumpers I25 at the lower left portion of the framev A, Fig. 4.

It is apparent that the danger of energizing the trip solenoid, I85 and releasing an empty conveyor B from the track '1? into the hoist frame A is avoided until the track portion 21 has reached the proper downward and leftward, limits of its movement, at which position the track portion 2'! will be aligned with the end of the incoming track T for receiving an empty conveyor B. Also even with the track 21 in its lower and leftward position, trip solenoid, I06 cannot be energized if limit switch I5I is tripped by a conveyor B already in position within the hoist frame A and adjacent the bumpers I25.

Upon satisfying the condition for closing switches I91, I'I'IA, and IEIA, solenoid I96 is energized and the walking beam escapement mechanism V is actuated to release an empty conveyor B, which rolls from the track T on the rail portion 21 and against the bumpers I25 where it trips limit switch i5I, opening switch I5IA and also closing the circuit through the right relay 205. The opening of switch IIiIA de-energizes the trip solenoid I96 so as to reset the walking beam escapement mechanism V to hold a subsequent empty conveyor B in readiness for release into the hoist frame A when the solenoid I96 is subsequently energized. The energizing of the right relay 205 closes the normally open relay switch 206 which by-passes limit switch I5I, opens the normally closed relay switch 201 which is in series with the left relay 208, and closes the three normally open right relay switches I84 which cause the traversing motor to move the carriage W and conveyor B now carried on the track 21 to the right in Fi 4.

As the carriage W moves to the right, it rides oil limit switch I", and the conveyor B rides off limit switch I5I. Thus limit switch I5I opens and the switch I5IA associated therewith closes. Limit switch I'I'I closes and its associated switch IIIA opens. Since relay switch 200 now bypasses limit switch I5I, the opening of the latter does not interrupt the circuit through the righ relay 205. Also the closing of limit switch I'I'I does not close the circuit through the left relay 208 because the normally closed relay switch 201 is now open.

The empty conveyor B continues to move to the right in Fig. 4 until it reaches the block loading position whereat the carriage W trips and opens the normally closed limit switch I53. The opening of limit switch I53 de-energizes the right relay 205, permitting the closing of the normally closed relay switch 201, the opening of the normally open relay switch 206, and the opening of the three normally open right relay switches I84, which latter action stops the conveyor B at its loading position.

With the conveyor B at its loading position, blocks H from the block-making machine C are carried by the chain conveyor I immediately above the parallel shelf portions 25 which comprise the conveyors top shelf J. The chain I preferably extends into the block receiving, end of the conveyor B for essentially the entire length thereof and operates in synchronism with the machine C so that as each block H is completed, it is transferred while still on its pallet from the molding machine C to the chain conveyor I. The latter moves forward block by block to provide room for each succeeding block until the chain conveyor I is completely loaded as in Fig. 3. c

When the foremost block H onthe chain conveyor I reaches the rear of the conveyor B, it trips the normally open limit switch I55, energizing relay 2I3 which closes the normally open relay switch 2| 4 in the circuit for the up re-' lay 2| 5. The energizing of the up relay 2I5 closes the normally open relay switch 2I6 ln'the by-pass circuit for the relay switch 2| 4, opens the normally closed relay switch 2I1 in series with the down relay 202, and closes the three normally open up relay switches I85 in the circuit for the hoist motor 69, causing the latter to raise the conveyor B.

As the conveyor B is raised, the block H which has tripped limit switch I55 rides oif that switch, opening the circuit through relay 213 and causing relay switch 2I4 to reopen. The opening of relay switch 2 I4 does not de-energize the up relay 2I5 because relay switch 2I4 is now bypassed by the closed relay switch 216.

When conveyor B has been raised through an increment equal to the vertical spacing of the shelves J, the normally closed limit switch 156 is tripped and opened by the uppermost dog I22 on the hoist control shaft II6. Thus the circuit through the up relay 2I5 is broken, the-three normally open up switches I85 open, and the conveyor B stops with its second shelf J from the top in the position formerly occupied by the uppermost shelf J prior to the hoisting operation, i. e., slightly below the upper surface of the conveyor chain I. The second shelf J from the top is then loaded by an essential repetition of the hoisting cycle, the conveyor chain I being first loaded, limit switch I55 being then tripped,

conveyor B being then raised until the second dog I22 from the top on shaft II6 trips limit switch I56 and stops conveyor B with its third shelf in the loading position.

The loading procedure is repeated until each shelf J is loaded. In the present instance, the conveyor B shown has five shelves J and four. dogs I22 so that the fifth hoisting operation continues until the rail 21 is aligned with the discharge rail K, at which position both limit switches I56 and I51 are tripped by the projection I24 provided by the lower portion of the shaft I I6. The opening of limit switch I56 stops the upward movement of the conveyor B as heretofore described. The closing of the normally open limit switch I51 closes the circuit through the solenoid 2I8 which actuates the aforementioned air valve for the pneumatic ram I58 and causes extension of the plunger arm I64. The loaded conveyor B is thus pushed on the rail K by the flanged head I68 of the push-off rod I66. The conveyor B then rolls by gravity along the track K to the bridge crane M. The loaded conveyor B is then transported to the treating kilns where the blocks H are steam cured or otherwise treated while still on the conveyor B, and then conveyed to the storage yards via the rails R. The empty conveyor B is returned from the storage yards via the rails S and T to the 14 walking beam V and is held in readiness to reenter the frame A at the proper time.

As the conveyor B is pushed on the tramrail K, the arm I65 trips and closes the normally open limit switch I13. The closing of the switch I13 while limit switch I51 is also closed energizes the relay 2I9, which closes the normally open relay switch 222 in the by-pass circuit of limit switch I13, opens the normally closed relay switch 223 in series with the air valve solenoid 2l8 for ram I58, and closes the normally open relay switch 224 in the circuit for the lef relay 208.

The de-energizing of air valve solenoid 2I0 upon the opening of switch 223 causes retraction of the plunger arm I64, permitting the normally open limit switch I13 to reopen, but relay 2I9' is not de-energized because limit switch I13 is by-passed by relay switch 222.- Am I64 remains retracted until limit switch I51 is again closed upon a subsequent operation of the loading cycle.

The energizing of the left relay 208 closes the normally open relay switch 225 in the by-pass circuit for relay switch 224, opens the norm-ally closed relay switch 226 in the circuit for the right relay 205, and closes the three normally open left relay switches I83 in the circuit for the traversing-motor 65. Thus the traversing motor 65 is energized to drive the carriage W to the left, releasing limit switch I51 to its normal open position.

The opening of limit switch I51 de-energlzes relay 2I9, permitting the normally open relay switches 222 and 224- to reopen, and the normally closed relay switch 223 to close. The opening of relay switch 224 does not ole-energize the left relay 208 since switch 224 is now by-passed by relay switch 225. Also, the closing of relay switch 223 does not re-energize the air valve solenoid 2 IB because limit switch I51 is nowopen.

Near the middle of the leftward movement of the carriage W, limit switch I15 is tripped by contact with beam 29 to close the circuit through the down relay 202. The energizing of the down relay 202 closes the normally open relay switch 221 in the by-pass circuit for the limit switch I15, opens the normally closed relay switch I91 inseries with both the up relay 2I5. and trip solenoid I96, and closes the three normally open down relay switches I86 in the circuit for the hoist motor 69. Thus hoist motor 69 is energized to lower the hoisting shafts 66 and track 21. As the conveyor B moves down and rides off limit switch I15, the opening of that switch does not break the circuit through the down relay 202 since limit switch I15 is now by-passed by relay switch 221.

When the carriage W has moved to the desired leftward limit, the normally closed limit switch I11 in series with the now closed relay switch 225 is tripped by contact with the underportion of the carriage W to open the circuit through the left relay 208 and to stop the traversing motor 65, and also to close the associated switch I11A in the circuit for the trip solenoid I96. In addition to opening the three normally open left relay switches I83 in the circuit for the traversing motor 65, the de-energizing of relay 208 closes the normally closed relay switch 226 in the circuit for the right relay 205, and opens the normally open relay switch 225 in the by-pass circuit fo relay switch 224. 1

When the downward movement of the track,

21 has continued to the desired lower limit, the topof the hoist control shaft II6 will have been lowered below the normally closed limit switch I19, releasing and opening that switch which is otherwise held closed by contact with the shaft H6, thereby de-energizing the down relay 292. The de-encrgizing of the down relay 262 opens the normally open relay-switch 221 in the by-pass circuit for the limit switch H5, closes the normally closed relay switch I91 in series with the "up relay 2I5 and the trip solenoid I96, and opens the three normally open down relay switches I86 which stop the hoist motor 6% The track 21 having reached its desiredlower and leftward limits in alignment with the incoming rail T, so that switches I91 and Il'IA are closed, and with switch I5IA closed, there being no conveyor B in the frame A to trip limit switch I5I, the trip coil I96 for the walking beam escapement mechanism V is energized and another empty conveyor B is permitted to roll from the track T to the track 2?. Upon entry of the second empty conveyor B into the frame A, limit switch I5I is again tripped and the traversing motor 65 is energized to drive the carriage W to the right, thereby starting a repeat cycle of automatic operations as above described.

It is to be noted from Fig. 9 that when the selector switch I92 is moved to the manual position 3, the various hoisting and traversing operations may be effected by the four normally open jog switches, 22B, 229, 232, and 233, which are associated respectively with the four normally closed jog switches 228A, 229A, 232A, and 233A, each of the four latter switches being opened when its associated jog switch is closed, thereby disconnecting the circuit controlled by the associated jog switch from automatic operation.

Upon closing jog switch 228, the circuit through the up relay 2I5 is closed and the hoist motor -69 is energized to raise track 21 as previously described if limit switch I56 is not open. Upon closing jog switch 229, the circuit through the down relay 202 is closed and the hoist motor 69 is energized to lower the track 21 as previously described if limit switch I19 is not open.

Upon closing the jog switch 232, the circuit through the left relay 298 is closed and the traversing motor 65 is energized to drive the carriage W to the left as previously described if limit switch ITI is not open. Upon closing the jog switch 233, the circuit through the right relay 205 is closed and the traversing motor is energized to drive the carriage W to the right as described above if limit switch I53 is not open.

I claim:

1. In a material handling system adapted for use with a block making machine and comprising a plurality of tram conveyors, a tram rail circuit starting at a loading point adjacent the discharge end of the block making machine and leading therefrom through a curing kiln and then returning to the starting point; tram conveyer handling means including a frame; a movable rail portion adapted to receive an empty tram conveyer at the rear of the said frame and move said empty tram conveyer transversely to a loading position at the front of said frame; screw-threaded hoisting shaft means affixed rigidly at one end to the top of said rail portion; a transversely movable carrier member actuated by an electric traversing motor and located atop said frame. said carrier member having internally screw threaded rotatable bushings which are immovable in a vertical direction, said bushings being adapted for rotation by an electric hoisting motor to move said hoisting shaft means vertically relative to said carrier member and bushings when said bushings are rotated; a hoist control shaft disposed adjacent said hoisting shaft means and movable therewith, said hoist control shaft having vertically spaceddogs disposed thereon and a projection disposed below said spaced dogs, said spaced dogs being, adapted to trip a limit switch to stop vertical movement of said hoisting shaft means at predetermined increments during loading of the: tram conveyor, and said projection being adapted to trip a limit switch to stop vertical movement of said hoisting shaft means at the upward limit of travel and at the same time actuate a push-off. mechanism to move a loaded, conveyor onto a tram rail leading to the curing kilns; means for returning said push-01f mechanism to its originalposition; means for actuating the traversing motor to return the said movable rail portion to the rear part of the frame; and means to actuate the hoisting motor and lower the rail portion tothe tram conveyer receiving position.

2. A device as claimed in claim 1 and further characterized in that the said vertically spaced dogs on said h ist control shaft are pivotally disposed in slots with the pivot point of each dog lying closer to the bottom of the respective slot than the top so that the dogs are held in an extended position against the bottom of the slot when the said hoist control shaft moves upward and are pivotally moved into the said slots upon encountering any obstruction when the hoist control shaft moves downward.

3. Material handling device adapted to load and handle an empty material transporting unit, comprising a frame adapted to receive said material transporting unit, a receiving member disposed in said frame and adapted to engage said transporting unit, screw-threaded hoisting means affixed rigidly at one end to the top of said receiving member, a carrier member disposed atop said frame, internally screw-threaded rotatable bushings mounted on said carrier member and secured against vertical movement, an electric hoisting motor adapted to rotate said bushings and move said hoisting means vertically relative to said carrier member and bushings, a hoist control shaft disposed adjacent said hioisting means and movable therewith, said hoist control shaft having vertically spaced dogs disposed thereon and a projection disposed below said spaced dogs, a limit switch disposed on said carrier member and electrically connected with said hoisting motor, said spaced dogs being adapted to trip said limit switch to stop vertical movement of said hoisting means at predetermined increments during loading of the material transporting unit, and said projection bein adapted to trip said limit switch to stop vertical movement of said hoisting means at the upward limit of travel, and means to actuate said hoisting motor and lower said receiving member to its initial position.

4. A device as claimed in claim 3 and further characterized in that the said vertically spaced 17 when the said hoist control shaft moves upward and are pivotally moved into the said slots upon encountering any obstruction when the hoist control shaft moves downward.

WALTER A. GRUENEBERG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 445,939 Monk Feb. 3, 1891 857,143 Zagelmeyer June 18, 1907 1,320,707 Pauly Nov. 4, 1919 1,350,604 Graham Aug. 24, 1920 1,491,771 Fuller Apr. 22, 1924 Number 15 Number Name Date Castleman Sept. 16, 1924 Schroeder et a1. Dec. 9, 1924 Rapp Mar. 23, 1926 McClelland Nov/9, 1926 Hanley, Jr. Sept. 6, 1927 Pelton Dec. 24, 1929 Henderson Dec-8, 1931 Hoch July 2, 1935 Weise Mar. 24, 1936 Freyssinet Nov. 16, 1937 Henderson Nov. 5, 1940 FOREIGN PATENTS Country Date Germany Dec. 2, 1908 

